I can't believe people are really saying football in the parity, salary cap era. Every year there's teams that are successful out of nowhere. Shizlansky was right, Any Given Sunday, look at those Giants squads. Okay yeah its a huge roster and a hard cap, but only highly dysfunctional organizations like the Browns seem to be ALWAYS putting awful teams out there. That says something imho.
Basketball you need The Guy to win a title ofc but its easy to make the playoffs if you actually want to.
Baseball imho is the hardest because of the whole minor league/farm system dynamic. It just moves in slow motion compared to the others. In football and basketball, there's a draft that can change your fortunes pretty much overnight if you get lucky enough. That's IMPOSSIBLE in baseball, when you draft somebody you gotta wait like 4 years before they're even ready to be a Rookie on a major league field. Hell, look at the Phillies. Their old GM made a bunch of flashy trade moves for elite talent, but depleted the farm system in doing so. Now they gotta spend YEARS in the desert while they re-stock the cupboard and hope the new farm talent develops into something. Shit's brutal.